foo.cc: In function 'int main()':
foo.cc:9:8: warning: init-statement in selection statements only available with -std=c++1z or -std=gnu++1z
     if(0<=a&&0=b&&300
        ^
foo.cc:9:19: error: lvalue required as left operand of assignment
     if(0<=a&&0=b&&300
                   ^~~
foo.cc:17:2: error: expected primary-expression before 'return'
  return 0;
  ^~~~~~
foo.cc:17:2: error: expected ')' before 'return'
foo.cc:7:13: warning: unused variable 'c' [-Wunused-variable]
     int a,b,c;
             ^

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